The invention is based on a container lid with an opening device. A lid of this kind known for instance from European Patent A-0004834 comprises a relatively thick, outer carrier layer of thermoplastic material and a thin, inner barrier layer of an aluminum/plastic laminate. To facilitate opening a container that is sealed with a lid of this kind, a weakening line i.e., a line of semiperforations, a fold or a score-line that weakens the material along the line is disposed in the carrier layer of the lid, surrounding a tear-open part.
Despite the weakened or even completely perforated carrier layer in the area of the tear-open part, very much greater force must be exerted to make the initial tear when tearing out the tear-open part from the container lid than to continue tearing open the part. Accordingly, it is desirable to have a container lid of the generic type described above that could be embodied such that easy initial tearing and continuation of the tear is attained.